Answer:
$87,696
Step-by-step explanation:
your father wants to get the same distribution during the whole 25 years that he is retired, but we must first determine the initial adjusted to inflation. The $55,000 that he currently earns will be equivalent to $55,000 x (1 + 3%)¹⁰ = $73,915.40 in 10 years.
Since your father wants to start collecting the distributions immediately after he retires, this is an annuity due. Using the present value of an annuity due formula, we can determine the money that he will need to have in 10 years.
PV = annual distribution x annuity factor
- annual distribution = $73,915.40
- PV annuity due factor, 25 periods, 4% = 16.24696
PV = $73,915.40 x 16.24696 = $1,200,900.55
That PV now becomes our future value that must be saved.
Since your father already has $100,000 in his account, that will turn into $100,000 x (1 + 4%)¹⁰ = $148,024.43
This means that he is $1,200,900.55 - $148,024.43 = $1,052,876.12 short.
Using the future value of an ordinary annuity formula, we can determine his annual contribution:
annual contribution = FV / annuity factor
FV = $1,052,876.12
FV annuity factor, 4%, 10 periods = 12.006
annual contribution = $1,052,876.12 / 12.006 = $87,695.83 ≈ $87,696